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<meta property="og:description" content="操作系统        进程与线程的联系与区别： 线程是资源分配的最小工作单元，进程是程序执行的最小单元； 进程使用独立的数据空间，而线程共享进程的数据空间。   Linux常用命令 awk&#x2F;top&#x2F;netstat&#x2F;grep&#x2F;less&#x2F;tail                        网络知识">
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window.CONFIG = CONFIG;</script><meta name="generator" content="Hexo 6.3.0"></head><body><div class="container" id="container"><header class="header" id="header"><div class="header-inner"><nav class="header-nav header-nav--fixed"><div class="header-nav-inner"><div class="header-nav-menubtn"><i class="fas fa-bars"></i></div><div class="header-nav-menu"><div class="header-nav-menu-item"><a class="header-nav-menu-item__link" href="/"><span class="header-nav-menu-item__icon"><i class="fas fa-home"></i></span><span class="header-nav-menu-item__text">首页</span></a></div><div class="header-nav-menu-item"><a class="header-nav-menu-item__link" href="/archives/"><span class="header-nav-menu-item__icon"><i class="fas fa-folder-open"></i></span><span class="header-nav-menu-item__text">归档</span></a></div><div class="header-nav-menu-item"><a class="header-nav-menu-item__link" href="/categories/"><span class="header-nav-menu-item__icon"><i class="fas fa-layer-group"></i></span><span class="header-nav-menu-item__text">分类</span></a></div><div class="header-nav-menu-item"><a class="header-nav-menu-item__link" href="/tags/"><span class="header-nav-menu-item__icon"><i class="fas fa-tags"></i></span><span class="header-nav-menu-item__text">标签</span></a></div><div class="header-nav-menu-item"><a class="header-nav-menu-item__link" href="/about/"><span class="header-nav-menu-item__icon"><i class="fas fa-address-card"></i></span><span class="header-nav-menu-item__text">关于</span></a></div></div><div class="header-nav-mode"><div class="mode"><div class="mode-track"><span class="mode-track-moon"></span><span class="mode-track-sun"></span></div><div class="mode-thumb"></div></div></div></div></nav><div class="header-banner"><div class="header-banner-info"><div class="header-banner-info__title">ljyxsg的技术成长录</div><div class="header-banner-info__subtitle">亿点点nice的ljy</div></div></div></div></header><main class="main" id="main"><div class="main-inner"><div class="content-wrap" id="content-wrap"><div class="content" id="content"><!-- Just used to judge whether it is an article page--><div id="is-post"></div><div class="post"><header class="post-header"><h1 class="post-title">java面试汇总</h1><div class="post-meta"><span class="post-meta-item post-meta-item--createtime"><span class="post-meta-item__icon"><i class="far fa-calendar-plus"></i></span><span class="post-meta-item__info">发表于</span><span class="post-meta-item__value">2023-01-27</span></span><span class="post-meta-item post-meta-item--updatetime"><span class="post-meta-item__icon"><i class="far fa-calendar-check"></i></span><span class="post-meta-item__info">更新于</span><span class="post-meta-item__value">2023-02-10</span></span></div></header><div class="post-body">
        <h5 id="操作系统"   >
          <a href="#操作系统" class="heading-link"><i class="fas fa-link"></i></a><a href="#操作系统" class="headerlink" title="操作系统"></a>操作系统</h5>
      <ul>
<li>进程与线程的联系与区别：<ul>
<li>线程是资源分配的最小工作单元，进程是程序执行的最小单元；</li>
<li>进程使用独立的数据空间，而线程共享进程的数据空间。</li>
</ul>
</li>
<li>Linux常用命令<ul>
<li>awk&#x2F;top&#x2F;netstat&#x2F;grep&#x2F;less&#x2F;tail</li>
</ul>
</li>
</ul>

        <h5 id="网络知识"   >
          <a href="#网络知识" class="heading-link"><i class="fas fa-link"></i></a><a href="#网络知识" class="headerlink" title="网络知识"></a>网络知识</h5>
      <ul>
<li>TCP特点：基于链接(点对点)；双工通信；可靠传输；拥塞控制；基于字节流而非报文</li>
<li>TCP实现细节：8种报文状态；滑动窗口机制；KeepAlive</li>
</ul>

        <h5 id="设计模式"   >
          <a href="#设计模式" class="heading-link"><i class="fas fa-link"></i></a><a href="#设计模式" class="headerlink" title="设计模式"></a>设计模式</h5>
      <ul>
<li>不同的设计模式在不同场景中的应用<ul>
<li>1、工厂模式：Spring如何创建Bean</li>
<li>2、代理模式：Motan服务的动态代理</li>
<li>3、责任链模式：Netty消息处理的方式</li>
<li>4、适配器模式：SLF4J如何支持Log4J</li>
<li>5、观察着模式：GRPC是如何支持流式请求的</li>
<li>6、构造者模式：PB对象使用builder</li>
</ul>
</li>
<li>单例模式<ul>
<li>1、静态初始化(饿汉式)</li>
<li>2、双重检查（懒汉式）</li>
<li>3、单例注册表</li>
</ul>
</li>
</ul>

        <h5 id="java语言特性"   >
          <a href="#java语言特性" class="heading-link"><i class="fas fa-link"></i></a><a href="#java语言特性" class="headerlink" title="java语言特性"></a>java语言特性</h5>
      <ul>
<li><p>HashMap:</p>
<ul>
<li><p>数组加链表的实现方式：</p>
<p>​		数组中的每一项是一个链表。通过计算存入对象的 HashCode，来计算对象在数组中要存入的位置，用链表来解决散列冲突，链表中的节点存储的是键值对。</p>
</li>
<li><p>容量大小为2的幂次方的原因</p>
<p>​		可以通过按位与操作来计算余数，比求模要快。</p>
</li>
<li><p>并发读写会有什么风险</p>
<p>​		HashMap 是非线程安全的，在多线程 put 的情况下，有可能在容量超过填充因子时进行 rehash，因为 HashMap 为了避免尾部遍历，在链表插入元素时使用头插法，多线程的场景下有可能会产生死循环</p>
</li>
</ul>
</li>
<li><p>ConcurrentHashMap（阅读源码）:</p>
<ul>
<li>并发控制与分段锁思想</li>
<li>1.8中的CAS自旋锁</li>
<li>红黑树的启用条件</li>
</ul>
</li>
<li><p>版本特性</p>
<ul>
<li><p>1.8：</p>
<ul>
<li>Lambda表达式</li>
<li>Stream API</li>
<li>方法引用</li>
<li>接口默认方法</li>
<li>Metaspace替换PermGen</li>
</ul>
</li>
<li><p>1.9-1.10:</p>
<ul>
<li>模块系统</li>
<li>默认G1回收器</li>
<li>接口私有方法</li>
<li>局部变量推断</li>
<li>Graal编译器</li>
</ul>
</li>
<li><p>1.11</p>
<ul>
<li>ZGC</li>
<li>字符串API增强</li>
<li>内建HTTP Client</li>
</ul>
</li>
</ul>
</li>
</ul>

        <h1 id="加分项"   >
          <a href="#加分项" class="heading-link"><i class="fas fa-link"></i></a><a href="#加分项" class="headerlink" title="加分项"></a>加分项</h1>
      <ul>
<li>1、知识点与典型的业务场景关联</li>
<li>2、用反例来描述实际场景中误用的危害</li>
<li>3、与知识点相关的优化点</li>
<li>4、与支持点相关的最新技术趋势</li>
<li>5、在了解的前提下，尽量增加回答内容深度</li>
</ul>
</div><footer class="post-footer"><div class="post-ending ending"><div class="ending__text">------ 本文结束，感谢您的阅读 ------</div></div><div class="post-copyright copyright"><div class="copyright-author"><span class="copyright-author__name">本文作者: </span><span class="copyright-author__value"><a href="https://lou_jianyang.gitee.io">ljyxsg</a></span></div><div class="copyright-link"><span class="copyright-link__name">本文链接: </span><span class="copyright-link__value"><a href="https://lou_jianyang.gitee.io/2023/01/27/%E8%AE%A1%E7%AE%97%E6%9C%BA%E5%9F%BA%E7%A1%80%E5%92%8Cjava%E8%AF%AD%E8%A8%80%E7%89%B9%E6%80%A7/">https://lou_jianyang.gitee.io/2023/01/27/%E8%AE%A1%E7%AE%97%E6%9C%BA%E5%9F%BA%E7%A1%80%E5%92%8Cjava%E8%AF%AD%E8%A8%80%E7%89%B9%E6%80%A7/</a></span></div><div class="copyright-notice"><span class="copyright-notice__name">版权声明: </span><span class="copyright-notice__value">本博客所有文章除特别声明外，均采用 <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/deed.en" rel="external nofollow" target="_blank">BY-NC-SA</a> 许可协议。转载请注明出处！</span></div></div><nav class="post-paginator paginator"><div class="paginator-prev"><a class="paginator-prev__link" href="/2023/01/28/rpc%E6%9E%B6%E6%9E%84%E8%AE%BE%E8%AE%A1/"><span class="paginator-prev__icon"><i class="fas fa-angle-left"></i></span><span class="paginator-prev__text">rpc架构设计</span></a></div><div class="paginator-next"><a class="paginator-next__link" href="/2023/01/27/webservice%E6%A1%86%E6%9E%B6jersey/"><span class="paginator-prev__text">webservice框架jersey</span><span class="paginator-next__icon"><i class="fas fa-angle-right"></i></span></a></div></nav></footer></div></div></div><div class="sidebar-wrap" id="sidebar-wrap"><aside class="sidebar" id="sidebar"><div class="sidebar-nav"><span class="sidebar-nav-toc current">文章目录</span><span class="sidebar-nav-ov">站点概览</span></div><section class="sidebar-toc"><ol class="toc"><li class="toc-item toc-level-5"><a class="toc-link" href="#%E6%93%8D%E4%BD%9C%E7%B3%BB%E7%BB%9F"><span class="toc-number">1.</span> <span class="toc-text">
          操作系统</span></a></li><li class="toc-item toc-level-5"><a class="toc-link" href="#%E7%BD%91%E7%BB%9C%E7%9F%A5%E8%AF%86"><span class="toc-number">2.</span> <span class="toc-text">
          网络知识</span></a></li><li class="toc-item toc-level-5"><a class="toc-link" href="#%E8%AE%BE%E8%AE%A1%E6%A8%A1%E5%BC%8F"><span class="toc-number">3.</span> <span class="toc-text">
          设计模式</span></a></li><li class="toc-item toc-level-5"><a class="toc-link" href="#java%E8%AF%AD%E8%A8%80%E7%89%B9%E6%80%A7"><span class="toc-number">4.</span> <span class="toc-text">
          java语言特性</span></a></li></ol></li></ol></li></ol></li></ol></li><li class="toc-item toc-level-1"><a class="toc-link" href="#%E5%8A%A0%E5%88%86%E9%A1%B9"><span class="toc-number"></span> <span class="toc-text">
          加分项</span></a></section><!-- ov = overview--><section class="sidebar-ov hide"><div class="sidebar-ov-author"><div class="sidebar-ov-author__avatar"><img class="sidebar-ov-author__avatar_img" src="/images/icons/stun-logo.svg" alt="avatar"></div><p class="sidebar-ov-author__text">Hello Stun</p></div><div class="sidebar-ov-state"><a class="sidebar-ov-state-item sidebar-ov-state-item--posts" href="/archives/"><div class="sidebar-ov-state-item__count">15</div><div class="sidebar-ov-state-item__name">归档</div></a><a class="sidebar-ov-state-item sidebar-ov-state-item--categories" href="/categories/"><div class="sidebar-ov-state-item__count">9</div><div class="sidebar-ov-state-item__name">分类</div></a><a class="sidebar-ov-state-item sidebar-ov-state-item--tags" href="/tags/"><div class="sidebar-ov-state-item__count">2</div><div class="sidebar-ov-state-item__name">标签</div></a></div><div class="sidebar-ov-cc"><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/deed.en" target="_blank" rel="noopener" data-popover="知识共享许可协议" data-popover-pos="up"><img src="/images/cc-by-nc-sa.svg"></a></div></section><div class="sidebar-reading"><div class="sidebar-reading-info"><span class="sidebar-reading-info__text">你已阅读了 </span><span class="sidebar-reading-info__num">0</span><span class="sidebar-reading-info__perc">%</span></div><div class="sidebar-reading-line"></div></div></aside></div><div class="clearfix"></div></div></main><footer class="footer" id="footer"><div class="footer-inner"><div><span>Copyright © 2023</span><span class="footer__icon"><i class="fas fa-heart"></i></span><span>ljyxsg</span></div><div><span>由 <a href="http://hexo.io/" title="Hexo" target="_blank" rel="noopener">Hexo</a> 强力驱动</span><span> v6.3.0</span><span class="footer__devider">|</span><span>主题 - <a href="https://github.com/liuyib/hexo-theme-stun/" title="Stun" target="_blank" rel="noopener">Stun</a></span><span> v2.8.0</span></div></div></footer><div class="loading-bar" id="loading-bar"><div class="loading-bar__progress"></div></div><div class="back2top" id="back2top"><span class="back2top__icon"><i class="fas fa-rocket"></i></span></div></div><script src="https://cdn.jsdelivr.net/npm/jquery@v3.4.1/dist/jquery.min.js"></script><script src="https://cdn.jsdelivr.net/npm/velocity-animate@1.5.2/velocity.min.js"></script><script src="https://cdn.jsdelivr.net/npm/velocity-animate@1.5.2/velocity.ui.min.js"></script><script src="/js/utils.js?v=2.8.0"></script><script src="/js/stun-boot.js?v=2.8.0"></script><script src="/js/scroll.js?v=2.8.0"></script><script src="/js/header.js?v=2.8.0"></script><script src="/js/sidebar.js?v=2.8.0"></script></body></html>